1. Field
Example embodiments of the present invention relate to a communication method in a wireless communication system, and more specifically to a communication method in a wireless communication system in which at least one time division duplexing (TDD) carrier and at least one frequency division multiplexing (FDD) carrier are aggregated.
2. Description of Related Art
In a cellular communication environment, a general method for exchanging data between terminals is a communication method via a base station. That is, if a first terminal has data to be transmitted to a second terminal, the first terminal transmits the data to a first base station to which it belongs. Then, the first base station transmits the data received from the first terminal to a second base station to which the second terminal belongs through a core network. At last, the second base station transmits the data received from the first base station to the second terminal. Here, the first base station and the second base station may be same, or may be different.
A carrier aggregation (CA) technique may be introduced into such the cellular communication system. The CA technique means a technique which configures a single wide-band by aggregating a plurality of component carriers (CC). In the conventional CA based wireless communication system, only component carriers based on a same duplexing mode are aggregated. That is, the conventional system is configured by aggregating only TDD-mode component carriers or by aggregating only FDD-mode component carriers.
On the other hand, hybrid automatic repeat request (HARQ) timing scheme should be redesigned in the CA between a TDD cell and a FDD cell because a frame structure of the TDD cell is different from a frame structure of the FDD cell.